Records are there to be broken, but some are more resilient than others. Australian scrum-half George Gregan has held the all-time world record for the number of international appearances since he overtook Jason Leonard in June 2006, and looks safe for at least another year.

The closest challengers to Gregan's 139 caps are two Irishmen - Brian O'Driscoll and Ronan O'Gara, both on 126. O'Driscoll might be reckoned the better bet to get there first, since he's likelier to be able to add Lions caps next summer. O'Gara is also two years older, but misses fewer matches through injury and has a bloody-minded indestructibility that might just sustain him for longer.

Should either of them overtake Gregan, it will be a case of the record returning home. Where the all-time points record, currently held by Dan Carter, has been shared around the major nations, that for most appearances has been much more concentrated, and nowhere has held it longer than Ireland.

As with the points record, constructing a sequence of record holders involves making some tricky judgments, in particular over treatment of French players whose total included matches against 'minor' nations at a time when other countries did not count them. But those judgments come well down the line from the international game's foundation in 1871.

You might expect one of the players in that inaugural Scotland v England match to have been first to the landmark figure of 10 caps and founder of our line. Instead it was a comparative latecomer. Blackheath forward Max Marshall did not make his debut until 1873 but, aided by rapid changes elsewhere in the England team and the fact that Scotland was later starting fixtures against Ireland, was first to double figures by the Ireland match in 1878.

This also proved to be his last game and he was overtaken a year later by one of the veterans of 1871, Scotland forward Robert 'Bulldog' Irvine. England was not to recapture the record for 125 years, while Irvine's 11th cap inaugurated a Scottish dominance of the record that was to last for the rest of the nineteenth century.

All three Scottish record-holders were Academicals. Irvine, who won his first cap at 17 and was recalled by historian RJ Phillips as 'a very strong man' and 'among the greatest figures in the early days of the game' was an Edinburgh Accie. His medical career meant that he won his 13th and last when he was only 26, leaving a mark of 13 caps that fell to his club-mate William MacLagan in 1884.

MacLagan, a winger, was to be the first long-term holder of the record and to date the only one to lose, then regain the title. His missing the 1886 season allowed John Brown,a durable Glasgow Accies forward, to squeeze past him when winning his 19th and final cup in that year's Calcutta Cup match.

Brown's distinction was short-lived. MacLagan returned for the following year and won his 20th cap when Scotland entertained Wales, a match which also lives on in the record books for the five tries scored by Scotland's George Lindsay in a 12-try massacre about which Welsh historians are wont to remain silent. MacLagan, a ferociously competitive player recalled by Irvine as having 'roughness often imputed to him' and more bluntly by an unnamed team-mate as 'an ill-natured devil' ran up a final total of 29 caps, the last three as captain of the first Lions team to visit South Africa in 1891.
That was enough to keep him top of the list until 1900, when the Scottish Accies gave way to the Welsh All Whites. First of the memorable Swansea duo who between them kept the record until 1928 was flamboyant fullback Billy Bancroft - already the all-time leading points scorer - who won his 30th cap when Wales completed their second Triple Crown in Belfast in 1900. Ending on 33 caps a year later, he was finally overtaken by his club-mate Dickie Owens, the inventor of modern scrum-half play, who won his 34th cap at Twickenham in 1912 in the final season of an international career that eventually amounted to 36 caps. In 1914 Welshmen held seven of the top 10 positions in the all-time caps list.

But they in time gave way to the Irish - and in particular Ulstermen. First up was threequarter George Stephenson, who won his 37th cap against France on the last day of 1928 and then overtook Billy Bancroft's younger brother Jack as the record points scorer on the day when he won his 42nd and last cap in 1930.

Quite who took those records from him is a matter for debate. What is not in question is that he held both for longer than any other player in rugby history. The French would argue a strong case for one of their giants, Jean Prat, who won his 43rd cap in 1954 under memorable circumstances, scoring the winning try in their first ever victory over the All Blacks. But 11 of those matches did not count, in the eyes of other nations,as full internationals.

"That every single record holder until then had come from one of the Five Nations was no fluke. Not until professionalisation and the coming of the Tri-Nations did southern hemisphere players get as many international chances."

The official narrative would instead rank Ken Jones, the Welsh winger who won a sprint relay medal at the 1948 Olympics, next in line. His 43rd cap, including three for the Lions, came at Twickenham in January 1956. Irish outside-half Jack Kyle, like Stephenson a medic trained at Queen's University, Belfast, tied Jones on 44 caps five weeks later, but did not overtake him until February 1957, shortly after the Welsh wing played his 47th and final Test. Kyle went on for a further year, overtaking Prat's final mark when he played his 52nd and last international on March 1, 1958.

Next up, through French eyes, was flanker Michel Crauste, who ran up a total of 63 caps (43 to the British) before his retirement in 1965. But the rest of the world continued to recognise Irish record-holders.

Kyle was not overtaken until 1971, when fullback Tom Kiernan won his 53rd cap. His appearance in the list is notable not only for the shortest reign as record-holder - a mere six weeks - but a rare incursion by a Munsterman into more than 60 years of dominance by Ulstermen.

It was Willie John Bride who, with Kiernan briefly out of the side, restored the red-handed status quo by winning his 54th cap against Wales in March 1971. And it was nearly 20 years before it went elsewhere. The giant Ballymena lock took his final total to 80 caps (including 17 for the Lions). That mark fell in turn to another Ulsterman, Mike Gibson - inheritor of Kyle's twin attributes of durability and creative genius - when he played his 81st and last international against Australia in 1979.

Gibson stayed atop the list through the 1980s, during which the rest of the world began to follow French in awarding caps for all appearances against other national teams. So when exuberant fullback Serge Blanco won his 82nd cap for France against Scotland in January 1991, few disputed his place at the top of the all-time list.

Blanco's Test career concluded exactly nine months and 11 caps later, in France's brutally tense home defeat by England in the quarter-final of the World Cup at the Parc des Princes.
It was another Frenchman who overtook Blanco a little more than two years later, when Philippe Sella won his 94th cap. The brilliant centre became the first player to win 100 caps in June 1994 when France played the All Blacks in Christchurch and like Blanco bowed out with a World Cup tie against England, the abysmal third place match at Pretoria in June 1995.

On the opposing side that day was Jason Leonard, who was to overtake Sella in yet another World Cup match, winning his 112th England and Lions cap against Georgia in October 2003. As well as being the first specialist prop, and the first Englishman for more than a century, the amiable Barking man was also the first man on this list to get there with the help of replacement appearances, with 15 in his final tally of 119.

That every single record holder until then had come from one of the Five Nations was no fluke. Not until professionalisation and the coming of the Tri-Nations did southern hemisphere players get as many international chances. Once they did, the breakthrough was made with Gregan's 120th appearance, against England in June 2006.

Only six of Gregan's eventual total of 139 caps were won as a replacement, but if O'Driscoll remains a first choice (which seems likely) and fit (less certain), his record of 133 starts may go first. All but one of Driscoll's 126 caps have been won as a starter. A trouble-free autumn programme and Five Nations might just see him end the home season level with Gregan's mark as a starter and ready to take it outright next summer in Australia.

Holders of the most-capped Test player record sequence:(with final Test cap totals)